Premature birth is the biggest cause of infant mortality worldwide, yet most of those deaths could be readily prevented, according to a 2 May report from the World Health Organization (WHO) and child-health advocacy groups. The report summarizes the results of a comprehensive survey of the problem, and says that pre-term births are on the rise —a worrying trend — but that low-income countries could reduce deaths among these infants by introducing a few affordable key health-care practices.